1670987 has 4 divisors (see below), whose sum is σ = 1675296. Its totient is φ = 1666680.

The previous prime is 1670983. The next prime is 1671041. The reversal of 1670987 is 7890761.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7890761 = 281 ⋅28081.

It is a cyclic number.

It is not a de Polignac number, because 1670987 - 2² = 1670983 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1670987.

It is not an unprimeable number, because it can be changed into a prime (1670983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1508 + ... + 2369.

It is an arithmetic number, because the mean of its divisors is an integer number (418824).

2^1670987 is an apocalyptic number.

1670987 is a deficient number, since it is larger than the sum of its proper divisors (4309).

1670987 is an equidigital number, since it uses as much as digits as its factorization.

1670987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4308.

The product of its (nonzero) digits is 21168, while the sum is 38.

The square root of 1670987 is about 1292.6666236892. Note that the first 4 decimals coincide. The cubic root of 1670987 is about 118.6654681878.

The spelling of 1670987 in words is "one million, six hundred seventy thousand, nine hundred eighty-seven".